I'm working on a crawl space encapsulation. One of the last steps for me to do is to setup a dehumidifier. I bought a Santa Fe Compact 70 and a condensate pump to go with it. I'm discharging it about 20 feet away.

It feels as though I didn't really plumb the condensate pump correctly. Here is my setup.

  1. Dehumidifier setup (note, any extension cord you see is temporary only). The condensate pump has a check valve in it and a barbed fitting to a 3/8" ID clear vinyl tube.

  2. I then take that up to my floor joist and create an inverted U as specified by the instructions (basically only thing the instructions say to do).

  3. I then come down and transition to a 1/2" PVC pipe with a barbed fitting. This is my first question. Is it okay that I go from a barbed fitting at the condensate pump to a vinyl tube then have a second barbed fitting that transitions to a PVC pipe? It seems as though this second barbed fitting would create a bit of a bottle neck.

  4. I then have roughly 18' of PVC pipe that has plenty of fall to it. The end of the PVC is at least 1 foot lower than the start

  5. I then transition back to a vinyl tube using a third barbed fitting and into the sump pit

Here is a rough drawing of what I have

Is it bad for me to have those barbed fittings? I could get rid of the third barbed fitting if I wanted to and just stay straight PVC into the sump pit, but the vinyl tubing was easier to work with.

The condensate pump doesn't appear to be working as I would expect. After the highest point, water is sitting in the vinyl tube right before the transition to the PVC pipe. I can see some air pockets as well. I understand that water will be trapped between the highest point and the condensate pump, which is fine because there is a check valve. But I would expect all of the water after the highest point to be drained out by gravity. Here is a quick video of me running the condensate pump where you can see the water sitting near the transition to the PVC pipe and not draining. Here is a quick video of the water exiting the PVC pipe and transitioning to the vinyl tube and into the sump pit.

Any reason why this isn't draining well at all?

  • does the pump's tank still drain each time it runs? no problem if so.
    – dandavis
    Jun 29, 2021 at 4:20
  • if it bothers you, you can likely make it drain by placing a drop of Dawn in the pump tank to break the surface tension of the water, for a while at least...
    – dandavis
    Jun 29, 2021 at 22:33

2 Answers 2


It looks to me as if the condensate pump is operating correctly. If it empties the reservoir then let it alone. As far as the water staying in the tubing, there is not enough natural gravity to pull the water out of the tubing. The tubing at the pump stays full because of the pumps check valve . To me it looks like it is working correctly so I say don't overthink it. My 2 cents.


Do not try to equate what you see with working properly.

Have you ever seen a steel plate with holes floating on water? The same thing is happening in the tubing--the water tension is holding the water from draining.

When the pump is running everything is working properly and this is a very normal setup. If you want to see the water move it may take a 1/2 hour without pressure in some cases if ever for it to drain on its own.

Nothing wrong here and when the pump is running everything is working as advertised.

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